Process of reducing iron oxids.



HORACE W. LASH, OF CLEVELAND, OHIO.

PROCELSS OF REDUCING IRON QXIDS- Specification of Letters Patent.

Patented June 11, 1907.

Application filed October 13, 1905. Renewed April 8, 1907- Serial No- 3To to whom it may concern: Be it known that I, HORACE W. LAsn,-a citizenof the United States, residing at Cleveland, in the county of Cuyahogaand State of Ohio, have invented a certain new and useful Improvement inProcesses of Reducing Iron Oxids, of which the following is a full,clear, and exact description, reference beingliad to the accompanyingdrawings.

My invention relates to the reduction of iron oxids to the condition offinished steel or to a partially refined metal suitable for the makingof castings.

In the history of the art many attempts have been made to obtain ironfrom its ores without smelting the latter in the blast furnace, but asis known to everyone conversant with the matter, every attempt hitherto.has failed signally and no process has hitherto been discovered whichhas been commercially operative or successful. Ihave, however, in myprocess, many times obtained all of the irontheoretically possible toobtain from the charge and have uniformly secured over 98 per cent.ofthe theoretical amount.

In carrying out my process I avail myselfof the conditions prevailing inan electric furnace and use a charge comprising finely divided iron oxidmixed with finely divided cast or pig iron and finely divided carbon;-the proportions of the various ingredients being'such as indicatedbelow. I may also use a certain quantity of flux of such an amount asmay be necessary from the nature of the charge and find that a markedadvantage derived from the addition of a small quantity of sawdust orequivalent material.

As it is necessary to have the iron oxid in a finely divided condition,the process is well adapted. to the use of magnetic concentrates.

The metallic portion of the charge may be sh'otted or granulated cast orpig iron, or finely divided cast iron obtained from any source. It is,however, to be noted that this iron must be of the quality commonlydesignated as cast, or pig iron, as distin uished from the ordinary runof scrap, wroug t iron, or steel, since it is important, that it containa high percentage of metalloids or easily oxidizable metals such asmanganese, capable of uniting with the oxygen of the ore.

The carbon to be added is referably in the form of ordinarycoke and isel ground,

as are the other portions of the c arge. I

also preferably add a small proportion of readily combustible materialsuch as crushed coal or sawdust. This latter addition is for the purposeof rendering the mass porous owing to its combustion taking place at anearly stage of the process thereby leaving unfilled intersticesthroughout the mass' These various materials, together with suitableflux, are intimately mixed, either by grinding in a dry or wet pan, orby any other suitable means which will bring the particles into intimatecontact. A binder may be added, if desired.

The prepared charge, either in the form of lumps, briquets, or 1n aloose condition, is charged into a suitable electric furnace, and thetemperature raised to smelting heat. Under the influence of the heat,the sawdust or other readily combustible material, if present,disappears as such, leaving the niass to a certain extent porous. Uponthe continued application of heat the metalloids and easily oxidizablemetals contained in the cast iron and a portion of the carbon of thecarbonaceous additions unite with the oxygen of the oxids present, thusreducing the iron of such oxids to metallic condition. The flux presentperforms its usual function and the entire quantity of iron, both thecast iron originally added and the iron reduced from the ores, is foundin the form of a-fused bath, containing a certain amount of metalloidswhich m:' y be eliminated tothe extent desired, by the usual treatment.By carrying on this operation in an electric furnace, the metalloids ofthe cast iron and the added carbon are protected from wastefuloxidation, since there is no flame or current of oxidizing gas flowingacross the charge, the atmosphere above the bath being practicallyneutral.

Percentage iron obtained from total amcimt presamt in charge.

Charge.

16. 00 ore 16. 00 cast iron 2. 00 carbon .50 lime stone 50 fluor spar 50sawdust 98 1 per cent.

whatever oxidation not preferable.

Charge. 7

12. ore

6.00 cast iron' 2. 00 carbon 25 lime stone 2 fiuor-spar 50 sawdust 21.O0 18. OO 7. 0O 2. O0 25 comes necessary to use a greater proportionfrom total amount pres ent in charge;

100. per cent.

ore

cast iron carbon -lime stone fiuor spar sawdust 100. per cent.

' of cast iron, which for commercial reasons is The presence of the freecar-- bon, added preferably in the form of coke, seems to have theeffect of protecting the metalloids contained in the cast iron againstmight possibly occur, thereby enabling said metalloids to be utilized asreducing agents for the iron oXid.

Percentage iron obtaimd by the atmosphere' Having thus described myinvention, I claim 1 1 The method-of reducing iron oxids comprising.intimately mixing finely divided oxid of iron with finely divided .castiron and carbonaceous material, charging the same into.

an electric furnace and subjecting the mixtureto a'smeltin heat.

2. The metho ofreducing iron oxids consistin in forming a char e ofintimately miXe finely divided cast iron and. oXid of iron withadditional carbonaceous and fluxes, chargingthe same into an electricfurnace, and sub3ecting the charge to a smelting heat in a non-oxidizingatmosmaterial ere. v 3. The method of'reducing iron oxids comprisingsubjecting a mixture of finely divided oxid of iron and finely dividedcast iron and carbonaceous material to a smelting heat in anon-oxidizing atmosphere.

4-. The method of reducing iron oxid's consisting in forming a chargecomprising a'mixture of finely divided oxid, finely divided cast iron,carbon, and finely ground, readily combustible material, chargin thesame into an electric furnace, and su jecting the same to a smeltingtemperature. a

In testimony whereof, I hereunto aifixmy signature in the presence oftwo Witnesses.

HORACE W. LASH'.

Witnesses:

J M'. WoonwARn, E; B. GILOHRIST.

